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    <li class="nav-header no-margin-top">
      <div class="ttip" data-toggle="tooltip" data-placement="bottom" title="The date that this version of boolean was released.">
      <span class="relatize">08 Jul 2016 17:14:57 UTC</span>
    </li>
  <li>
    Distribution: <a href="https://metacpan.org/dist/boolean">boolean</a>
  </li>
  <li>
    Module version: 0.46
  </li>
  <li>
    <a data-keyboard-shortcut="g s" href="https://metacpan.org/dist/boolean/source/lib/boolean.pm">Source</a>
    (<a href="https://metacpan.org/dist/boolean/source/lib/boolean.pm?raw=1">raw</a>)
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  <li>
    <a data-keyboard-shortcut="g p" href="https://metacpan.org/dist/boolean/source/lib/boolean.pod">Pod Source</a>
    (<a href="https://metacpan.org/dist/boolean/source/lib/boolean.pod?raw=1">raw</a>)
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  <li>
    <a data-keyboard-shortcut="g b" href="https://metacpan.org/dist/boolean/source/lib">Browse</a>
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      <a rel="noopener nofollow" class="nopopup" href="https://github.com/ingydotnet/boolean-pm">Homepage</a>
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        <a rel="noopener nofollow" data-keyboard-shortcut="g r" href="https://github.com/ingydotnet/boolean-pm">Repository</a>
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      <a rel="noopener nofollow" data-keyboard-shortcut="g i" href="https://github.com/ingydotnet/boolean-pm/issues">Issues</a>
      (5)
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    <li>
      <a rel="noopener nofollow" href="http://matrix.cpantesters.org/?dist=boolean+0.46" title="Matrix">Testers</a>
        <span title="(pass / fail / na)">(<a rel="noopener nofollow" href="https://www.cpantesters.org/distro/b/boolean.html?oncpan=1&amp;distmat=1&amp;version=0.46&amp;grade=2" style="color: #090">1446</a> / <a rel="noopener nofollow" href="https://www.cpantesters.org/distro/b/boolean.html?oncpan=1&amp;distmat=1&amp;version=0.46&amp;grade=3" style="color: #900">1</a> / <a rel="noopener nofollow" href="https://www.cpantesters.org/distro/b/boolean.html?oncpan=1&amp;distmat=1&amp;version=0.46&amp;grade=4">0</a>)</span>
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    <li>
      <a rel="noopener nofollow" href="http://cpants.cpanauthors.org/release/INGY/boolean-0.46">Kwalitee</a>
    </li>
    <li>
      <div class="ttip" data-toggle="tooltip" data-placement="bottom" title="The # people with an indexing permission on boolean who have released something to CPAN in the last 2 years (i.e. the # people likely able to release critical fixes in a timely manner)">
      Bus factor: 2
      </div>
    </li>
    <li>
      <a rel="noopener nofollow" href="http://cpancover.com/latest/boolean-0.46/index.html">80.77% Coverage </a>
    </li>
    <li>
      License: perl_5
    </li>
    <li>
      Perl: v5.8.1
    </li>
    <li class="nav-header">Activity</li>
    <li>
<div class="activity-graph">
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    <div class="comment">24 month</div>
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<select onchange="document.location.href=&#39;/release/&#39;+this.value+&#39;/view/lib/boolean.pm&#39;" class="form-control tool-bar-form">
  <option disabled selected>Jump to version</option>
<option
  disabled
  value="INGY/boolean-0.46"
>0.46
  (INGY on 2016-07-08)</option>
<option
  
  value="INGY/boolean-0.45"
>0.45
  (INGY on 2015-02-05)</option>
<optgroup label="BackPAN">'
<option
  
  value="INGY/boolean-0.44"
>0.44
  (INGY on 2015-01-31)</option>
<option
  
  value="INGY/boolean-0.43"
>0.43
  (INGY on 2015-01-01)</option>
<option
  
  value="INGY/boolean-0.42"
>0.42
  (INGY on 2014-08-16)</option>
<option
  
  value="INGY/boolean-0.41"
>0.41
  (INGY on 2014-08-16)</option>
<option
  
  value="INGY/boolean-0.40"
>0.40
  (INGY on 2014-08-09)</option>
<option
  
  value="INGY/boolean-0.39"
>0.39
  (INGY on 2014-08-02)</option>
<option
  
  value="INGY/boolean-0.38"
>0.38
  (INGY on 2014-06-26)</option>
<option
  
  value="INGY/boolean-0.37"
>0.37
  (INGY on 2014-06-25)</option>
<option
  
  value="INGY/boolean-0.36"
>0.36
  (INGY on 2014-06-25)</option>
<option
  
  value="INGY/boolean-0.35"
>0.35
  (INGY on 2014-06-17)</option>
<option
  
  value="INGY/boolean-0.34"
>0.34
  (INGY on 2014-06-14)</option>
<option
  
  value="INGY/boolean-0.33"
>0.33
  (INGY on 2014-06-14)</option>
<option
  
  value="INGY/boolean-0.32"
>0.32
  (INGY on 2014-02-09)</option>
<option
  
  value="INGY/boolean-0.31"
>0.31
  (INGY on 2014-02-07)</option>
<option
  
  value="INGY/boolean-0.30"
>0.30
  (INGY on 2013-04-03)</option>
<option
  
  value="INGY/boolean-0.29"
>0.29
  (INGY on 2013-04-02)</option>
<option
  
  value="INGY/boolean-0.28"
>0.28
  (INGY on 2011-09-12)</option>
<option
  
  value="INGY/boolean-0.27"
>0.27
  (INGY on 2011-06-28)</option>
<option
  
  value="INGY/boolean-0.26"
>0.26
  (INGY on 2011-01-20)</option>
<option
  
  value="INGY/boolean-0.25"
>0.25
  (INGY on 2011-01-15)</option>
<option
  
  value="INGY/boolean-0.24"
>0.24
  (INGY on 2011-01-13)</option>
<option
  
  value="INGY/boolean-0.23"
>0.23
  (INGY on 2010-09-17)</option>
<option
  
  value="INGY/boolean-0.22"
>0.22
  (INGY on 2010-09-15)</option>
<option
  
  value="INGY/boolean-0.21"
>0.21
  (INGY on 2010-09-15)</option>
<option
  
  value="INGY/boolean-0.20"
>0.20
  (INGY on 2008-08-25)</option>
<option
  
  value="INGY/boolean-0.12"
>0.12
  (INGY on 2008-06-04)</option>
<option
  
  value="INGY/boolean-0.11"
>0.11
  (INGY on 2007-06-11)</option>
<option
  
  value="INGY/boolean-0.10"
>0.10
  (INGY on 2007-06-10)</option>
</optgroup>
</select>
    </li>
    <li class="version-diff">
<select onchange="document.location.href='/release/INGY/boolean-0.46/diff/' + encodeURIComponent(this.value) + '/lib/boolean.pm'
" class="form-control tool-bar-form">
  <option disabled selected>Diff with version</option>
<option
  disabled
  value="INGY/boolean-0.46"
>0.46
  (INGY on 2016-07-08)</option>
<option
  
  value="INGY/boolean-0.45"
>0.45
  (INGY on 2015-02-05)</option>
<optgroup label="BackPAN">'
<option
  
  value="INGY/boolean-0.44"
>0.44
  (INGY on 2015-01-31)</option>
<option
  
  value="INGY/boolean-0.43"
>0.43
  (INGY on 2015-01-01)</option>
<option
  
  value="INGY/boolean-0.42"
>0.42
  (INGY on 2014-08-16)</option>
<option
  
  value="INGY/boolean-0.41"
>0.41
  (INGY on 2014-08-16)</option>
<option
  
  value="INGY/boolean-0.40"
>0.40
  (INGY on 2014-08-09)</option>
<option
  
  value="INGY/boolean-0.39"
>0.39
  (INGY on 2014-08-02)</option>
<option
  
  value="INGY/boolean-0.38"
>0.38
  (INGY on 2014-06-26)</option>
<option
  
  value="INGY/boolean-0.37"
>0.37
  (INGY on 2014-06-25)</option>
<option
  
  value="INGY/boolean-0.36"
>0.36
  (INGY on 2014-06-25)</option>
<option
  
  value="INGY/boolean-0.35"
>0.35
  (INGY on 2014-06-17)</option>
<option
  
  value="INGY/boolean-0.34"
>0.34
  (INGY on 2014-06-14)</option>
<option
  
  value="INGY/boolean-0.33"
>0.33
  (INGY on 2014-06-14)</option>
<option
  
  value="INGY/boolean-0.32"
>0.32
  (INGY on 2014-02-09)</option>
<option
  
  value="INGY/boolean-0.31"
>0.31
  (INGY on 2014-02-07)</option>
<option
  
  value="INGY/boolean-0.30"
>0.30
  (INGY on 2013-04-03)</option>
<option
  
  value="INGY/boolean-0.29"
>0.29
  (INGY on 2013-04-02)</option>
<option
  
  value="INGY/boolean-0.28"
>0.28
  (INGY on 2011-09-12)</option>
<option
  
  value="INGY/boolean-0.27"
>0.27
  (INGY on 2011-06-28)</option>
<option
  
  value="INGY/boolean-0.26"
>0.26
  (INGY on 2011-01-20)</option>
<option
  
  value="INGY/boolean-0.25"
>0.25
  (INGY on 2011-01-15)</option>
<option
  
  value="INGY/boolean-0.24"
>0.24
  (INGY on 2011-01-13)</option>
<option
  
  value="INGY/boolean-0.23"
>0.23
  (INGY on 2010-09-17)</option>
<option
  
  value="INGY/boolean-0.22"
>0.22
  (INGY on 2010-09-15)</option>
<option
  
  value="INGY/boolean-0.21"
>0.21
  (INGY on 2010-09-15)</option>
<option
  
  value="INGY/boolean-0.20"
>0.20
  (INGY on 2008-08-25)</option>
<option
  
  value="INGY/boolean-0.12"
>0.12
  (INGY on 2008-06-04)</option>
<option
  
  value="INGY/boolean-0.11"
>0.11
  (INGY on 2007-06-11)</option>
<option
  
  value="INGY/boolean-0.10"
>0.10
  (INGY on 2007-06-10)</option>
</optgroup>
</select>
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      <a href="https://metacpan.org/release/INGY/boolean-0.46/view/lib/boolean.pm">This version</a>
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<div class="plussers">
<div class="nav-header">++ed by:</div>
<div>
<a class="display-all" href="https://metacpan.org/author/RWP"><img src="https://www.gravatar.com/avatar/7110eb2389e69a066d9d7cad7a1cc2bf?d=identicon&amp;s=20" title="RWP" alt="RWP"></a>
<a class="display-all" href="https://metacpan.org/author/SKAUFMAN"><img src="https://www.gravatar.com/avatar/2caf2787e235f58a65576632f93ef6c3?d=identicon&amp;s=20" title="SKAUFMAN" alt="SKAUFMAN"></a>
<a class="display-all" href="https://metacpan.org/author/FPL"><img src="https://www.gravatar.com/avatar/5495dcfcab287b441b966df1a47cca74?d=identicon&amp;s=20" title="FPL" alt="FPL"></a>
<a class="display-all" href="https://metacpan.org/author/BKB"><img src="https://www.gravatar.com/avatar/191945c6c283d81db701008b2d89b68c?d=identicon&amp;s=20" title="BKB" alt="BKB"></a>
<a class="display-all" href="https://metacpan.org/author/TINITA"><img src="https://www.gravatar.com/avatar/41d992bb7c01d13ffb8b7bf1ed355e91?d=identicon&amp;s=20" title="TINITA" alt="TINITA"></a>
</div>
<!-- Display counts of plussers-->
<div>
    <a href="https://metacpan.org/dist/boolean/plussers">13 PAUSE users</a>
</div>
<div>
    8 non-PAUSE users
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  <span>
    <a data-keyboard-shortcut="g a" rel="author" href="https://metacpan.org/author/INGY" class="author-name">Ingy döt Net</a>
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  <span>&nbsp;/&nbsp;</span>
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<select onchange="document.location.href=&#39;/release/&#39;+this.value+&#39;/view/lib/boolean.pm&#39;" class="">
<option
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  value="INGY/boolean-0.46"
>0.46
  (INGY on 2016-07-08)</option>
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  value="INGY/boolean-0.45"
>0.45
  (INGY on 2015-02-05)</option>
<optgroup label="BackPAN">'
<option
  
  value="INGY/boolean-0.44"
>0.44
  (INGY on 2015-01-31)</option>
<option
  
  value="INGY/boolean-0.43"
>0.43
  (INGY on 2015-01-01)</option>
<option
  
  value="INGY/boolean-0.42"
>0.42
  (INGY on 2014-08-16)</option>
<option
  
  value="INGY/boolean-0.41"
>0.41
  (INGY on 2014-08-16)</option>
<option
  
  value="INGY/boolean-0.40"
>0.40
  (INGY on 2014-08-09)</option>
<option
  
  value="INGY/boolean-0.39"
>0.39
  (INGY on 2014-08-02)</option>
<option
  
  value="INGY/boolean-0.38"
>0.38
  (INGY on 2014-06-26)</option>
<option
  
  value="INGY/boolean-0.37"
>0.37
  (INGY on 2014-06-25)</option>
<option
  
  value="INGY/boolean-0.36"
>0.36
  (INGY on 2014-06-25)</option>
<option
  
  value="INGY/boolean-0.35"
>0.35
  (INGY on 2014-06-17)</option>
<option
  
  value="INGY/boolean-0.34"
>0.34
  (INGY on 2014-06-14)</option>
<option
  
  value="INGY/boolean-0.33"
>0.33
  (INGY on 2014-06-14)</option>
<option
  
  value="INGY/boolean-0.32"
>0.32
  (INGY on 2014-02-09)</option>
<option
  
  value="INGY/boolean-0.31"
>0.31
  (INGY on 2014-02-07)</option>
<option
  
  value="INGY/boolean-0.30"
>0.30
  (INGY on 2013-04-03)</option>
<option
  
  value="INGY/boolean-0.29"
>0.29
  (INGY on 2013-04-02)</option>
<option
  
  value="INGY/boolean-0.28"
>0.28
  (INGY on 2011-09-12)</option>
<option
  
  value="INGY/boolean-0.27"
>0.27
  (INGY on 2011-06-28)</option>
<option
  
  value="INGY/boolean-0.26"
>0.26
  (INGY on 2011-01-20)</option>
<option
  
  value="INGY/boolean-0.25"
>0.25
  (INGY on 2011-01-15)</option>
<option
  
  value="INGY/boolean-0.24"
>0.24
  (INGY on 2011-01-13)</option>
<option
  
  value="INGY/boolean-0.23"
>0.23
  (INGY on 2010-09-17)</option>
<option
  
  value="INGY/boolean-0.22"
>0.22
  (INGY on 2010-09-15)</option>
<option
  
  value="INGY/boolean-0.21"
>0.21
  (INGY on 2010-09-15)</option>
<option
  
  value="INGY/boolean-0.20"
>0.20
  (INGY on 2008-08-25)</option>
<option
  
  value="INGY/boolean-0.12"
>0.12
  (INGY on 2008-06-04)</option>
<option
  
  value="INGY/boolean-0.11"
>0.11
  (INGY on 2007-06-11)</option>
<option
  
  value="INGY/boolean-0.10"
>0.10
  (INGY on 2007-06-10)</option>
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<nav class="toc">
  <div class="toc-header"><strong>Contents</strong></div>
<ul>
  <li><a href="boolean.html#NAME">NAME</a></li>
  <li><a href="boolean.html#VERSION">VERSION</a></li>
  <li><a href="boolean.html#SYNOPSIS">SYNOPSIS</a></li>
  <li><a href="boolean.html#DESCRIPTION">DESCRIPTION</a></li>
  <li><a href="boolean.html#RATIONALE">RATIONALE</a></li>
  <li><a href="boolean.html#FUNCTIONS">FUNCTIONS</a></li>
  <li><a href="boolean.html#METHODS">METHODS</a></li>
  <li><a href="boolean.html#USE-OPTIONS">USE OPTIONS</a></li>
  <li><a href="boolean.html#DEPRECATIONS">DEPRECATIONS</a></li>
  <li><a href="boolean.html#JSON-SUPPORT">JSON SUPPORT</a></li>
  <li><a href="boolean.html#AUTHOR">AUTHOR</a></li>
  <li><a href="boolean.html#COPYRIGHT-AND-LICENSE">COPYRIGHT AND LICENSE</a></li>
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<div class="pod anchors">
<h1 id="NAME">NAME</h1>

<p>boolean - Boolean support for Perl</p>


<a href="https://travis-ci.org/ingydotnet/boolean-pm"><img alt="boolean-pm" src="https://travis-ci.org/ingydotnet/boolean-pm.png" /></a>

<h1 id="VERSION">VERSION</h1>

<p>This document describes <a href="https://metacpan.org/pod/distribution/boolean/lib/boolean.pod">boolean</a> version <b>0.46</b>.</p>

<h1 id="SYNOPSIS">SYNOPSIS</h1>

<pre><code>    use boolean;

    do &amp;always if true;
    do &amp;never if false;

    do &amp;maybe if boolean($value)-&gt;isTrue;</code></pre>

<p>and:</p>

<pre><code>    use boolean &#39;:all&#39;;

    $guess = int(rand(2)) % 2 ? true : false;

    do &amp;something if isTrue($guess);
    do &amp;something_else if isFalse($guess);</code></pre>

<h1 id="DESCRIPTION">DESCRIPTION</h1>

<p>Most programming languages have a native <code>Boolean</code> data type. Perl does not.</p>

<p>Perl has a simple and well known Truth System. The following scalar values are false:</p>

<pre><code>    $false1 = undef;
    $false2 = 0;
    $false3 = 0.0;
    $false4 = &#39;&#39;;
    $false5 = &#39;0&#39;;</code></pre>

<p>Every other scalar value is true.</p>

<p>This module provides basic Boolean support, by defining two special objects: <code>true</code> and <code>false</code>.</p>

<h1 id="RATIONALE">RATIONALE</h1>

<p>When sharing data between programming languages, it is important to support the same group of basic types. In Perlish programming languages, these types include: Hash, Array, String, Number, Null and Boolean. Perl lacks native Boolean support.</p>

<p>Data interchange modules like YAML and JSON can now <code>use boolean</code> to encode<i>decode</i>roundtrip Boolean values.</p>

<h1 id="FUNCTIONS">FUNCTIONS</h1>

<p>This module defines the following functions:</p>

<dl>

<dt id="true"><code>true</code></dt>
<dd>

<p>This function returns a scalar value which will evaluate to true. The value is a singleton object, meaning there is only one &quot;true&quot; value in a Perl process at any time. You can check to see whether the value is the &quot;true&quot; object with the isTrue function described below.</p>

</dd>
<dt id="false"><code>false</code></dt>
<dd>

<p>This function returns a scalar value which will evaluate to false. The value is a singleton object, meaning there is only one &quot;false&quot; value in a Perl process at any time. You can check to see whether the value is the &quot;false&quot; object with the isFalse function described below.</p>

</dd>
<dt id="boolean($scalar)"><a id="boolean"></a><a id="boolean-scalar"></a><code>boolean($scalar)</code></dt>
<dd>

<p>Casts the scalar value to a boolean value. If <code>$scalar</code> is true, it returns <code>boolean::true</code>, otherwise it returns <code>boolean::false</code>.</p>

</dd>
<dt id="isTrue($scalar)"><a id="isTrue"></a><a id="isTrue-scalar"></a><code>isTrue($scalar)</code></dt>
<dd>

<p>Returns <code>boolean::true</code> if the scalar passed to it is the <code>boolean::true</code> object. Returns <code>boolean::false</code> otherwise.</p>

</dd>
<dt id="isFalse($scalar)"><a id="isFalse"></a><a id="isFalse-scalar"></a><code>isFalse($scalar)</code></dt>
<dd>

<p>Returns <code>boolean::true</code> if the scalar passed to it is the <code>boolean::false</code> object. Returns <code>boolean::false</code> otherwise.</p>

</dd>
<dt id="isBoolean($scalar)"><a id="isBoolean"></a><a id="isBoolean-scalar"></a><code>isBoolean($scalar)</code></dt>
<dd>

<p>Returns <code>boolean::true</code> if the scalar passed to it is the <code>boolean::true</code> or <code>boolean::false</code> object. Returns <code>boolean::false</code> otherwise.</p>

</dd>
</dl>

<h1 id="METHODS">METHODS</h1>

<p>Since true and false return objects, you can call methods on them.</p>

<dl>

<dt id="$boolean-&gt;isTrue"><a id="boolean--isTrue"></a><code>$boolean-&gt;isTrue</code></dt>
<dd>

<p>Same as isTrue($boolean).</p>

</dd>
<dt id="$boolean-&gt;isFalse"><a id="boolean--isFalse"></a><code>$boolean-&gt;isFalse</code></dt>
<dd>

<p>Same as isFalse($boolean).</p>

</dd>
</dl>

<h1 id="USE-OPTIONS"><a id="USE"></a>USE OPTIONS</h1>

<p>By default this module exports the <code>true</code>, <code>false</code> and <code>boolean</code> functions.</p>

<p>The module also defines these export tags:</p>

<dl>

<dt id=":all"><a id="all"></a><code>:all</code></dt>
<dd>

<p>Exports <code>true</code>, <code>false</code>, <code>boolean</code>, <code>isTrue</code>, <code>isFalse</code>, <code>isBoolean</code></p>

</dd>
</dl>

<h1 id="DEPRECATIONS">DEPRECATIONS</h1>

<p>This module offered an export tag, <code>-truth</code>, that overrides the Perl interpreter&#39;s internal values for true and false. This has been found to corrupt the interpreter in some circumstances. Also, these overrides will no longer be possible as of Perl 5.22. Therefore, the <code>-truth</code> import tag is deprecated.</p>

<h1 id="JSON-SUPPORT"><a id="JSON"></a>JSON SUPPORT</h1>

<p>JSON::MaybeXS (or less preferably JSON.pm ) will encode Perl data with boolean.pm values correctly if you use the <code>convert_blessed</code> option:</p>

<pre><code>    use JSON::MaybeXS;
    use boolean -truth;
    my $json = JSON::MaybeXS-&gt;new-&gt;convert_blessed;
    say $json-&gt;encode({false =&gt; (0 == 1)});     # Says: &#39;{&quot;false&quot;:false}&#39;,</code></pre>

<h1 id="AUTHOR">AUTHOR</h1>

<p>Ingy d&ouml;t Net &lt;ingy@cpan.org&gt;</p>

<h1 id="COPYRIGHT-AND-LICENSE"><a id="COPYRIGHT"></a>COPYRIGHT AND LICENSE</h1>

<p>Copyright 2007-2016. Ingy d&ouml;t Net.</p>

<p>This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.</p>

<p>See <a href="http://www.perl.com/perl/misc/Artistic.html">http://www.perl.com/perl/misc/Artistic.html</a></p></div>

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